Biology
Gene Regulation and Mutation:
- Mutations May Cause Loss-of-function Or Gain-of-function
KEY TERMS:A null mutation completely eliminates the function of a gene. Leaky mutations leave some residual function, for instance when the mutant protein is partially active (in the case of a missense mutation), or when read-through produces a small...
- Mutations Are Concentrated At Hotspots
KEY TERMS:A hotspot is a site in the genome at which the frequency of mutation (or recombination) is very much increased, usually by at least an order of magnitude relative to neighboring sites. KEY CONCEPTS: The frequency of mutation at any particular...
- The Effects Of Mutations Can Be Reversed
KEY TERMS:Revertants are derived by reversion of a mutant cell or organism to the wild-type phenotype. Forward mutations inactivate a wild-type gene. A back mutation reverses the effect of a mutation that had inactivated a gene; thus it restores wild...
- Mutations May Affect Single Base Pairs Or Longer Sequences
KEY TERMS:A point mutation is a change in the sequence of DNA involving a single base pair. A transition is a mutation in which one pyrimidine is replaced by the other and/or in which one purine is replaced by the other. A transversion is a mutation...
- Mutations Change The Sequence Of Dna
KEY TERMS:Spontaneous mutations occur in the absence of any added reagent to increase the mutation rate, as the result of errors in replication (or other events involved in the reproduction of DNA) or by environmental damage. The background level of...
Biology
Progeria
Gene Regulation and Mutation:
Vocabulary:
-gene regulation: ability of an organism to control which genes are transcribed in response to the environment
-operon: section of DNA thatcontains the genes for the proteins needed for a specificmetabolic pathway
-mutation: a permanent change in the cell's DNA which changes either a single base pair or deletions of chromosomes
-Mutagen: a chemical that causes mutations
Summary:
Prokaryotic cells manage their protein synthesis through genes named operons. Then eukaryotic cells manage their protein synthesis using different transcriptions factore and RNA interferences. Mutations range from simple single base pairs to large deletions of chromosomes causing the DNA sequence to be adjusted and mutated. Mutagens can cause mutations in the DNA.
Progeria:
Progeria is a disorder that causes accelerated aging. Most children have progeria causing them to die around the age of 13, some even to their 20's because of a stroke or heart attack. When first born the child seems normal, but after a year you start seeing signs of the mutation. Such as, small jaw, nose, face and baldness. They also experience symptoms that older people have like joint stiffness or hip dislocation.
Luckily progeria isn't too common. It is estimated to effect one in 4 million newborns. The causes of progeria is a mutation of the Lamin A gene which causes devastating effects on cellular structure and function in children DNA. There still isn't a cure for Progeria, but research and surgeries are being conducted to find a cure.
- Mutations May Cause Loss-of-function Or Gain-of-function
KEY TERMS:A null mutation completely eliminates the function of a gene. Leaky mutations leave some residual function, for instance when the mutant protein is partially active (in the case of a missense mutation), or when read-through produces a small...
- Mutations Are Concentrated At Hotspots
KEY TERMS:A hotspot is a site in the genome at which the frequency of mutation (or recombination) is very much increased, usually by at least an order of magnitude relative to neighboring sites. KEY CONCEPTS: The frequency of mutation at any particular...
- The Effects Of Mutations Can Be Reversed
KEY TERMS:Revertants are derived by reversion of a mutant cell or organism to the wild-type phenotype. Forward mutations inactivate a wild-type gene. A back mutation reverses the effect of a mutation that had inactivated a gene; thus it restores wild...
- Mutations May Affect Single Base Pairs Or Longer Sequences
KEY TERMS:A point mutation is a change in the sequence of DNA involving a single base pair. A transition is a mutation in which one pyrimidine is replaced by the other and/or in which one purine is replaced by the other. A transversion is a mutation...
- Mutations Change The Sequence Of Dna
KEY TERMS:Spontaneous mutations occur in the absence of any added reagent to increase the mutation rate, as the result of errors in replication (or other events involved in the reproduction of DNA) or by environmental damage. The background level of...